ANTH 1001 Lecture Notes - Lecture 1: Sickle-Cell Disease, Allele Frequency, Genetic Drift
Document Summary
Evolution features: change in allele frequency, measured over generations, only concerns populations, microevolution vs. macroevolution. Original: the fat cat ate the wee rat. Point mutation: the fat hat ate the wee rat. The proportion of gametes carrying a newly arisen mutation at a given locus. Natural selection and population size determine whether a mutation will increase in frequency in a population. Those with alleles that enable them to strive to reproduce. Directional selection: one extreme end of range of variation favored. Disruptive selection: both extremes ends of the variation are favored over the average traits. Heterozygous- no/mild anemia (aa)- no malaria and mild anemia. Common in areas with a high incidence of malaria. Gene flow- introduction of alleles from on gene pool into another i. e. migration increasing diversity, less difference. Sickle cell anemia advantage in high malaria, disadvantage in low malaria area high sickle- cell anemia band from west africa to arabian peninsula.
